Can the President Impose Global Tariffs Under IEEPA? Supreme Court to Decide, Redefining Emergency Powers and Congressional Authority

The U.S. Supreme Court will hear oral arguments on November 5 to determine whether the president can impose broad tariffs under the International Emergency Economic Powers Act (IEEPA). The case tests the scope of emergency powers and the balance of presidential power in tariff policy.

A ruling could redefine whether executive action can bypass Congress by labeling economic threats as emergencies, with potential implications for the constitutional separation of powers and the durability of legislative checks in trade policy.

The dispute traces to former President Trump’s use of national emergency declarations to impose tariffs on Canada, Mexico, and China, along with a global 10% tariff and a 50% “matching tariff” for select countries. Courts and the Brennan Center filed amicus curiae briefs challenging IEEPA authority, arguing that long-standing trade imbalances do not constitute an emergency.

The court’s outcome will shape how emergency powers intersect with trade policy, informing risk assessments and regulatory planning for governments and market participants alike.